Field of the Invention
The invention relates to a transaxle including a hydrostatic transmission (hereinafter “HST”).
Related Art
Conventionally, as disclosed in U.S. 2015/0007555 A1, there is a well-known transaxle including a casing that carries an axle and that incorporates an HST and a gear train interposed between the HST and the axle. The HST includes a center section settled on a bottom of the casing via a fluid filter, a vertical axial hydraulic pump mounted on the center section, and a vertically slant axial hydraulic motor mounted on the center section.
A cavity of the casing has front and rear portions. One of the front and rear portions of the cavity serves as an HST chamber accommodating the HST, and the other of the front and rear portions of the cavity serves as a gear chamber accommodating the gear train and the axle. The hydraulic motor having a vertically and fore-and-aft slant axis is extended from the HST chamber into the gear chamber so as to be drivingly connected to the gear train in the gear chamber.
The fluid filter of the HST is submerged in a fluid sump in the cavity of the casing so as to charge the closed fluid circuit of the HST with fluid from the fluid sump. However, the HST chamber and the gear chamber are not partitioned from each other. In this state, a bottom portion of the gear train is also submerged in the fluid sump so that rotating gears agitate the fluid sump so as to tend to contaminate the fluid sump with air, thereby wrongly influencing activation of the HST and causing noise.